On-line navigation of mobile robot under the existence of dynamically moving multiple obstacles

This paper proposes an on-line navigation method of mobile robots for collision avoidance with dynamically moving obstacles, where the multiple obstacles always change their velocities. For more applications of mobile robots to real world, the robots are expected to work well in everyday space such that people are walking around. The robot must surely reach desired point even in the dynamical environment where many people (obstacles) are moving. In such situation that the environmental objects are dynamically changing it's position. It is not realistic to have all information of the dynamical environment such as trajectory of human being's motion. To cope with the situation, the robots usually have sensor system to get real time environmental information, and robots should have an ability of sensor-based on-line motion planning for the dynamical environment. The current paper issues the on-line motion planning problem where the workspace has multiple moving obstacles. The proposing motion planner basically uses an idea of Velocity Obstacle. After discussing some problems when applying the idea of Velocity Obstacle to on-line motion planning problem for dynamical environment, a modified method from the original method using the idea is presented. The main point of the modification is for coping with velocity changes of moving obstacles during sensor cycle. The paper also discusses an efficiency of resultant trajectory by the motion planner. Some simulations of on-line motion planning problem where multiple obstacles are changing their velocities are shown.